glow plugs.....

[relick62au]

I don't get it, I have had the head off for a few months, everything was running before but wanted to check it out and do valve stem seals. Anyways I get it back together today and I'll be buggered, wont start, not a single pop of ignition!!!
So I says to myself must be fuel, bleed the new injectors, na, nuthin, ok, bleed the pump just to be sure, na nuthin, winding winding winding over, nuthin...
Teenage son hounded me thru the whole episode (4hrs) about checking the glow plugs, so, ok, nuthin left to do, pull em out, they are all wet with fuel, put 12 volts on em, nuthin..... Not a single sizzle out of any of them, am I missing something here or should they not be getting HOT??
Question is, how could they all be stuffed at once, when everything was peachy prior. HHHHHEEEEEEEELLLLLLPPPPPP!!!!!

[fraser130]

Is this a series landy diesel?
If I remember correctly, the Glowplugs have two connections, and the earth is not one of them, so they are wired in series, so each one gets 3 volts, except there is also a resistor in the circut, which drops it further.
My memory os a little faded, but the thick wire comes from the resistor on the firewall then kinda zig-zags across all the glowplugs, with the last wire going to earth.....
So there is one connection at the tip, then an insulating ceramic washer, then another connection, then insulation, then the body (earth) which is not a connection..Clear as mud?

I'll see if I can confirm this somwhere and post back.


Does this picture help?





Fraser

[Blknight.aus]

if youve cranked it that much it'll start anyway.

the glow plug sequence (assuming you're using the genuine plugs) is in series and the body is not earthed.

DO not place a single glow plug across a 12v battery with out a current limiter or you will be puttin a new on in the hole you pulled it from. (It'll still work to seal the compression in tho)

a correct sequence for the wiring is

from the glowplug relay (or switch) to the resistor wire
a wire from the resistor wire to the bottom of glow plug 4
a ceramic insert
a wire from the top of glow plug 4 to the bottom of glow plug 3
a knurled locating nut

from there repeat the sequence but step the sequence relevent to the plugs the power coming from plug 4 rather than the resistor wire.

the last connector goes from the top of plug 1 to a good earth.

you only need one rough connection and it wont work.

what other work have you had done, might the pump timing or phasing be off?


IF after about 10 seconds of cranking with the fuel cut off in the run position and your foot flat on the floor if you're not huffing white smoke out the exhuast you've got serious compression issues and its not going to start.

[relick62au]

Hi Dave,

Well I've had em all on 12v so !! I would have sworn there was no wire coming off the last plug and going to earth but I could be wrong........
There certainly was not when I was trying to start it today. I put a multi meter on them in situ and they were getting 12v so??
As for work done it was purely head off, valves out, all good and put back together with new stem seals, head back on, make clearances 12 thou and here I am.
Do I need to do anything with timing the pump, hope not cause i've got no idea!?!?!?!

Russell.

[Blknight.aus]

again assuming you have the original series plugs and havent retrofitted normal 12v plugs.

if you dont have the earth lead your not going to be completing the 12v circuit

if you dont have the wiring hooked up properly then you dont complete the circuit (remeber theres 2 leads per plug)

if you put 12v onto the plug directly for long it will open circut and not work.

any chance of a pic of the wiring and a close up of the writing on the body of the plug?

[relick62au]

No pics but on the glow plugs is:
CORE 330 1.7V 3K
CORE 330 1.7V LRS 5H
CORE 330 1.7V 2G
133 B 1.7V LRG (NON MATCHING)

iT'S ALL APART AGAIN NOW AND i'M LOOKING FOR THAT LAST WIRE TO EARTH THE LAST PLUG........

[Blknight.aus]

they are the ones that you hook up in series (like the photo) I'll take some close ups of fozzys for you and draw up my suggested wiring diagram.

[fraser130]

Russell, when you measure the voltage, because there is no earth connected, you will get a 12v reading from all the plugs because there is no earth to pull the voltage down, but at least we know the realay and resistor is working, also, if they are wired correctly, (except the earth) then none of them are blown.
If you look closely at the plugs, there is a bronze part (one connection) and a threaded tip (the other connection).
The power has to flow through all of the plugs and eventually to earth.

so it will be resistor, bronze bit, tip to bronze, tip to bronze, tip to bronze, tip to earth, OR resistor , tip, bronze to tip, bronze to tip, bronze to tip, bronze to earth.
it all depends on where the wire from the resistor first goes to (which size hole it has on the wire) I wish I could remember where the earth was on mine, but it's been 12 years......

Fraser

[relick62au]

Thanks Fraser,

Mate, I cant remember what happened 12 days ago so I reckon your memory is not too bad!!
My main concern now in that in my ignorant bliss I have used jumper leads to connect each and every one to 12 volt, positive on threaded tip and negative on the body........ Being that I now know they dont earth thru the case am I out of the woods??
I cant believe I got the whole thing back together and I am missing one bloody wire, bugger. The fitting on the end of the wire coming from the resistor is the larger size so I had it all wired up fine but for that last connection to earth.
Now I am wondering what the difference is between them that is indicated by the last few letters in the numbers.
Many thanks to both you guys (Dave and Fraser) for your assistance. This would have ended with acquiring a car trailer and a trip to the Rover Doc. An episode that would have been a drama for me at present.

[relick62au]

Gentlemen, there is life!!!

All's is good, she is running although a little rough and still blowing blue/grey smoke intermittently but, at least I know what it isn't!!

Got her up to operating temp and re-tensioned the head. Is it really necessary to remove the injectors in order to re-tension the 2 bolts and 2 nuts that are below the injector bodies??

I guess the last thing to do is time the pump but I reckon I'll leave that for the pros.

Russell.